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Showing posts from August, 2015

Publication-quality matplotlib figures

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We're going to go from this... ... to this Install prettyplotlib , a useful tool for graph styling sudo pip install prettyplotlib    Add a new method to style the axes to prettyplotlib/util.py  def styling(ax, xpad=10.0, ypad=10.0, axiswidth=2.0, axistickwidth=2.0, axiscolor="#333333"):     for axis in ['bottom','left']: ax.spines[axis].set_linewidth(axiswidth)     for tick in ax.get_xaxis().get_major_ticks():         tick.set_pad(xpad)         tick.label1 = tick._get_text1()     for tick in ax.get_yaxis().get_major_ticks():         tick.set_pad(ypad)         tick.label1 = tick._get_text1()     ax.get_yaxis().set_tick_params(direction='out', width=axistickwidth)     ax.get_xaxis().set_tick_params(direction='out', width=axistickwidth)     ax.spines['bottom'].set_color(axiscolor)     ax.spines['left'].set_color(axiscolor)     ax.tick_params(axis='x', colors=axiscolor)     ax.tick_params(axis='y'

Merge force-fields in gromacs

Using gromacs with two force-fields are for ligand one for protein? Wanting to do that but not knowing how? Look no further. The technical problem is as follows: let's say you have your favourite custom force-field. For me it resides in charmm.ff and it's my hybrid charmm36+charmm22* set of parameters. To simulate a ligand inside of a system parametrized using the ff-above, I went to paramchem.org and obtained small molecule parameters for my ligand. These were in CHARMM format, so (courtesy of Alex Mackerell ) I converted those to gromacs itp files. That left me with a dependency on charmm36-jun2015.ff.tgz There is only a handful of lines I want from charmm36-jun2015.ff, the ligand is very simple. There is no easy way to get those out, or to merge my custom charmm with Alex's. Prerequisites Install networkx, a python package for dealing with graphs pip install networkx Let's take some example ligand molecules, such as the TPP - the ligand for EmrE drug tra